Nafion®/H-ZSM-5 composite membranes with superior performance for direct methanol fuel cells

All composite membranes have indeed lower methanol permeability and higher proton conductivity than pure DE2020 membrane. The composite membranes with Si/Al ratio 25 and 5 wt.% of zeolites (DEZ25-5) having the lowest methanol permeability and the membrane with Si/Al ratio 50 and 1 wt.% of zeolites (DEZ50-1) having the highest proton conductivity were tested in the DMFC for several days. The DEZ25-5 has the best performance; namely high power density and stable performance in time.